The present invention relates to an image processing device and an image processing method, particularly to an image processing device and an image processing method for identifying a pupil region.
Recently, there is developed a technology of automatically correcting a face image of a person captured by a digital camera or a camera-equipped mobile phone. In the face of the person, particularly an eye attracts attention of an observer of the image. As to correction performed to the eye, for example, it is conceivable to correct a red eye caused by a flash. There is also a technology of changing (improving) an appearance by enlarging the eye or a pupil in the face image. In the case that the eye or the pupil is corrected, a pupil region of the eye is accurately detected.
For example, a technology described in Patent Document 1 (Japanese Unexamined Patent Publication No. 2009-181424) is well known as a method for detecting a position of the pupil. In a configuration described in Patent Document 1, a circular pupil is detected using a Hough transform. At this point, using a difference in density gradient between the eye captured under near-infrared illumination and the eye captured under visible-light illumination, a fan-like voting region is set to control generation of a pseudo voting value peak.